Roller blinds are commonly used on windows and openings in walls of buildings to prevent or limit light intrusion, for privacy purposes, for insulating purposes, and generally to enhance esthetics. Traditionally, roller blinds have been operated through the use of a cord, chain or wand that operates a clutch to rotate a roller tube, in a first direction that causes a deployment of the blind, or in a second direction causing the blind to be retracted and stored upon the roller tube. Increasingly, the traditional cord, chain or wand has been replaced with the use of a small electric motor causing the roller tube to rotate in one direction or the other. In order to help maintain a low profile for the roller blind, motor manufacturers have developed motors having housings in the form of a relatively small diameter, elongate, tubular structure such that the motors can be received within an end of the blind's roller tube. The outer end of the motor is rigidly secured to an end bracket of the roller blind, with the inner end of the motor housing secured to, or otherwise capable of transmitting torque to, the roller tube, permitting the motor to rotationally drive the tube in a forward or backward direction. To accommodate motors of different lengths, and to permit the motor to be readily removed from within the roller tube for servicing, in many instances torque is transferred from the motor to the roller tube through a splined coupler on the motor that engages corresponding splines, ribs or channels within the interior of the roller tube.
Roller tubes incorporating such electric motors can make installation somewhat more difficult. The motors themselves can add significant weight to the roller blind, making it more difficult for an installer to hold the blind in place while it is being secured about a window or opening. Further, in instances where the blind is of a significant length, since the motor is positioned at one end of the roller tube, that end of the roller tube tends to be heavier than the opposite end. In the case of long roller tubes, this added weight can present further installation challenges for the installer. Since in most instances the motor is merely slid into an end of the roller tube, the installer must be careful not to lower the “motor end” of the tube to a point where the motor may slide longitudinally and fall from the end of the roller tube. If the motor were to fall the motor could cause damage to itself, to an object that it hits on its descent, or to individuals.